Lamp assembly for a light source

ABSTRACT

A light source includes a body with a cavity, a reflector which is disposed within the cavity, a lamp assembly which is disposed within the cavity and a focusing lens which is disposed within the cavity. The optical fiber is optically coupled to and axially aligned with the focusing lens of the light-tube module.

BACKGROUND OF THE INVENTION

The field of the invention relates to lamp assemblies for light sources.

In the prior art an illumination system includes a lamp assembly with alight bulb, a concave reflector, a fan and a bundle of optical fibers.The concave reflector condenses light energy and reflects it into thebundle of optical fibers. The fan dissipates the heat which the lightbulb generates. Due to the large size of the illumination system, it isusually located relatively far away from the work area. The remotepositioning of the illumination system necessitates the use of arelatively long bundle of optical fibers. Due to the light lossesinherent in the bundle of optical fibers, which losses can be as high asfifty percent per meter, the light bulb used must emit light of a highintensity and therefore, it must have a relatively high wattage. Onedisadvantage of using high wattage bulbs is that they have a relativelyshort operating life. Another disadvantage is that the high emission ofheat will inconvenience the operator as well as the patient.Furthermore, a relatively large fan must be used to cool theillumination system whereby the size of the fan creates an undesiredincrease in the overall size of the illumination system and producesdisturbing noise.

For many years, fiber optic illumination systems have used bundles ofoptical fibers to transmit light to dental and medical instruments. Oneend of each bundle of optical fibers is conventionally inserted into anopening in a socket which is aligned with a light source. The light fromthe light source is transmitted through the bundle of optical fibers tothe dental or medical instrument at the other end of the bundle ofoptical fibers.

European Patent Application filed Oct. 18, 1982 under Serial No.PCT/SE82/00337 discloses an illumination system which is relativelycompact and which includes a lens and reflector. The lens and thereflector are combined to form a condensing system which is designed toconcentrate light emitted from a relatively low wattage light bulb on alight-receiving end of a bundle of optical fibers. Because its light isconcentrated, the low wattage bulb can illuminate the light-receivingend of the bundle of optical fiber to the same extent as a higherwattage light bulb. The use of the low wattage light bulb isadvantageous in that it takes up less room and generates less heat thana high wattage light bulb. However, in order to illuminate more than onebundle of optical fibers and therefore more than one instrument, thelens of the condensing system is adapted so as to be switchable betweentwo or more bundles of optical fibers. Each bundle of optical fibers maybe selectively and independently coupled to the light bulb. Although theswitch permits a plurality of bundles of optical fibers to beilluminated, they can not be illuminated simultaneously. The provisionof such a light switch is also disadvantageous in that it requires amanual switching operation.

U.S. Pat. No. 3,758,951 teaches an illumination system which includes acontrol module for controlling the intensity of the light source. Thecontrol module is adapted to be mounted on a dental tray. The use of thecontrol module which is separate from the light source provides aconvenient mechanism for controlling the intensity of the light sourceand one which utilizes a minimum portion of a dentist's working area. Adental handpiece hose receives a bundle of optical fibers which isconnected to the light source. The dental handpiece hose includes theusual conduits and a further conduit disposed between conduits forreceiving the bundle of optical fibers. One of the walls defining thefurther conduit may be made up of a pair of elongated interlockingmembers which permit the wall to be partially or completely opened forready access to the further conduit.

U.S. Pat. No. 4,579,419 teaches a connector which includes an opticalfiber element having a light-receiving end with a transversecross-sectional shape which complements the transverse cross-sectionalshape of a light-receiving end of another optical fiber element. Thecomplementarily shaped light-receiving ends permit a plurality ofoptical fiber connectors to be arranged alongside one another so thatthey may be directly and simultaneously illuminated by a single beam oflight emitted from a source of light.

U.S. Pat. No. 3,638,013 describes an illumination system which includesa rotatable plug having three bundle-receiving openings. The plug may berotated so that one, two or all three of the openings are positioned tobe illuminated by a light source so that a corresponding number ofinstruments can be lit.

U.S. Pat. No. 4,208,579 teaches an apparatus for use in operating adental drill in which the air, water and light for the hand-held drillmember are each delivered from an associated supply source, all of whichare adapted to be located at a position remote from the working end ofthe drill and are coupled to the drill through a conduit cable. Acontrol mechanism for the selective energization of the light supplysource is located within easy reach of the operator to permit turn-onand/or turn-off of the light supply source through a simple fingertipcontrol which is provided within a remote control unit which is totallyelectrically isolated from the high voltage present in the light supplysource in order to protect both the operator and the patient from eithershock or injury. The light supply source may be automatically energizedmerely by lifting the dental instrument containing a bundle of opticalfiber. The apparatus may be independent of the dental drill in order topermit a wide variety of uses independently of its use with the dentaldrill.

U.S. Pat. No. 3,897,134 and U.S. Pat. No. 4,014,098 teach an opticalfiber element which includes a first bundle of optical fibers, a supportmember and a yieldable member. The first bundle of optical fibers has atleast two optical faces. The support member supports at least a portionof the bundle of optical fibers with one optical face in a desiredinitial position. The yieldable member cooperates with the first bundleof optical fibers in order to permit movement of one optical facerelative to its initial position upon application of pressure to oneoptical face. The optical fiber element is especially adapted for use incombination with a dental handpiece in a manner such that one opticalface extends through the turbine housing portion of the dentalhandpiece. The optical fiber element also includes a tubular guidemember, a resilient support member in the form of a flexible tubularmember and a plunger assembly. The first bundle of optical fibersextends through each of the above components. The other optical face ofthe optical fiber element is adapted to be coupled under compression andin face to face alignment with a light emitting face of a second bundleof optical fibers, which is connectable to a light source, to complete alight path to the light source.

The inventors incorporate the teachings of the above-cited patents intothis specification.

SUMMARY OF INVENTION

The present invention is generally directed to a lamp assembly for alight source. A connector connects the light source to a cable which hasan optical fiber.

In a first, separate aspect of the present invention, the light sourceincludes a housing and a light-tube module. The light-tube moduleincludes a body with a cavity, a reflector, a lamp assembly and afocusing lens. The reflector, the lamp assembly and the focusing lenssystem are disposed within the cavity of the body. The optical fiber isoptically coupled to and axially aligned with the focusing lens systemof the light-tube module.

Other aspects and many of the attendant advantages will be more readilyappreciated as the same becomes better understood by reference to thefollowing detailed description and considered in connection with theaccompanying drawing in which like reference symbols designate likeparts throughout the figures.

The features of the present invention which are believed to be novel areset forth with particularity in the appended claims.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective drawing of a dental video camera, a cable whichhas an optical fiber and a plurality of electrical wires and acombination light source and connector which includes a light sourcehaving a housing with a front, a side and a top, and a quickconnect/disconnect connector.

FIG. 2 is a front elevational view in partial cross-section of the frontof the housing of the light source of FIG. 1 taken along the line 2—2 ofFIG. 1.

FIG. 3 is a partial, exploded, top plan view in partial cross-section ofthe combination light source and connector of FIG. 1 with the housingalso having a bottom, a light-tube module, a circuit board and aprocessor being disposed on the bottom of the housing and the quickconnect/disconnect connector also having a socket and a heat sink.

FIG. 4 is a longitudinal view in cross-section of a light-tube module ofthe light source of FIG. 1 which includes a body with a cavity, atemperature sensor, a reflector, a lamp assembly having a plug accordingto the invention and a focusing lens system, also having a heat-sink andthe optical fiber of the cable of FIG. 1 taken along the line 4—4 ofFIG. 2.

FIG. 5 is a transverse view in cross-sections of the light-tube moduleof the combination light source and connector of FIG. 1 taken along theline 5—5 of FIG. 2.

FIG. 6 is a partial, top plan view in cross-section of the housing ofthe light source of FIG. 1.

FIG. 7 is an enlarged partial, longitudinal view in cross-section of thehousing of the light source of FIG. 1 taken along the line 7—7 of FIG.6.

FIG. 8 is a front elevational view in partial cross-section of a lightsource of FIG. 1 according to the invention.

FIG. 9 is schematic drawing of an electronic iris.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1 a combination light source and connector 10 whichincludes a light source 11 and a quick connect/disconnect connector 12,a dental video camera 13 and a cable 14. The cable 14 couples the dentalvideo camera 13 to the light source 11 through the connector 12. Theapplication which was filed under Ser. No. 08/560,397 teaches a dentalvideo camera which includes a housing CCD camera, an adjustably focusinglens, a fixed focusing lens system. The CCD camera is disposed withinthe proximal portion of the housing. The adjustably focusing lensincludes a first sleeve and a second sleeve. The first sleeve has alongitudinal axis. The first sleeve is axially aligned along thelongitudinal axis and is disposed within the elongated cavity of thehousing adjacent to the fixed focusing lens system. The first sleeve isable to rotate about the longitudinal axis and is restrained from movinglaterally back and forth along the longitudinal axis. The second sleeveis telescopically and slidably coupled to the first sleeve. The secondsleeve is able to move laterally back and forth along the longitudinalaxis and is restrained from rotating about the longitudinal axis. A knobbi-directionally drives the second sleeve laterally to produce back andforth lateral movements along the longitudinal axis, however a slidemechanism may bi-directionally drives the second sleeve laterally toproduce back and forth lateral movements along the longitudinal axis.The back and forth lateral movements of the second sleeve generatesclockwise and counter-clockwise rotations, respectively, of the firstsleeve. The adjustably focusing lens also includes a first achromaticlens, which is disposed in a first lens carrier, and a second achromaticlens, which is disposed in a second lens carrier. The first lens carrierwith the first achromatic lens is disposed within and coupled to thefirst sleeve. The second lens carrier with the second achromatic lens isdisposed within the first sleeve and is fixedly coupled to the firstsleeve. The back and forth lateral movements of the second sleevechanges the position of the first and second achromatic lenses withrespect to the position of the CCD camera thereby changing the field offocus. The adjustably focusing lens provides a focusing adjustmentbetween a near field of focus and a far field of focus. The dental videocamera also includes an electrically adjustable iris which is opticallyand mechanically coupled to the adjustably focusing lens system. Theelectrically adjustable iris is adjusted between a nearly closed openingand a wide open opening in response to the focusing adjustment betweenthe near field of focus and the far field of focus. When the knob is inthe neutral position the opening of the electrically adjustable iris isbetween nearly closed and wide open. When the knob has been rotatedcounter-clockwise forty five degrees from the neutral position theopening of the electrically adjustable iris is wide open.

U.S. Pat. No. 4,300,167 teaches an electrically adjustable iris which isa liquid crystal assembly forming at least a part of an image opticalsystem. The liquid crystal assembly consists of a plurality of liquidcrystals having a refractive index anisotropy and having differentresponse frequencies of molecule orientation so that the transmittivityand refractive index of the plurality of liquid crystals may beindependently controlled with few signal lines by varying the frequencyof the driving signal applied to the liquid crystal assembly. U.S. Pat.No. 4,431,288 teaches an electrically adjustable iris.

Referring to FIG. 1 in conjunction with FIG. 2 the light source 11includes a housing 15 with a front 16, a side 17, a top 18 and a bottom19 and a light-tube module 20 which includes a body 21 with a cavity 22,a reflector 23, a heat sensor 24, a lamp assembly 25 and a focusing lenssystem 26. The reflector 23, the heat sensor 24, the lamp assembly 25and the focusing lens system 26 are disposed within the cavity and areoptically aligned with each other.

Referring to FIG. 1 in conjunction with FIG. 3 the light source 11 alsoincludes a processor 27 and a circuit board 28. The light-tube module 20and the processor 27 are mechanically coupled to the bottom 19 of thehousing 15. The circuit board 28 is electrically coupled to theprocessor 27.

Referring to FIG. 1 in conjunction with FIG. 3 the cable 13 has aplurality of electrical wires 29 and an optical fiber 30.

Referring to FIG. 2 in conjunction with FIG. 3 the quickconnect/disconnect connector 12 has a plug 31, a socket 32 and a heatsink 33. The plug 31 has a bore 34 which receives the optical fiber 30.The plug 31 has a plurality of pins 35.

Referring to FIG. 3 in conjunction with FIG. 4 the socket 32 has athreaded bore 36. The socket 32 is mechanically coupled to the front 16of the housing 15. The plug 31 is adapted to be mechanically coupled tothe socket 32 so that the bore 34 of the plug 31 is axially aligned withthe threaded bore 36 of the socket 32. The socket 32 has a plurality ofreceptacles 37. Each pin 35 of the plug 31 is aligned with one of thereceptacles 37 of the socket 32 in order to receive it.

Still referring to FIG. 3 in conjunction with FIG. 4 the heat sink 33has a disc-shaped portion 38 with a first small bore 39 which receivesthe optical fiber 30 and a large bore 40 and a threaded stem portion 41with a second small bore 42 which receives the optical fiber 30. Thelarge bore 40 is axially aligned with the first small bore 39. Thedisc-shaped portion 38 of the heat sink 33 is slidably coupled withinthe cavity 22 of the body 21 of the light-tube module 20 and is disposedadjacent to the socket 32. The threaded stem portion 41 of the heat-sink33 is threadedly coupled in the threaded bore 36 of the socket 32. Theoptical fiber 30 is slidably coupled into the bore 34 of the plug 31 andthe first and second small bores 39 and 42 of the disc-shaped portion 38and the threaded stem portion 41, respectively, of the heat sink 33. Thethreaded stem portion 41 of the heat-sink 33 and the threaded bore 36 ofthe socket 32 do not have to be threaded. The quick connect/disconnectconnector 12, the iris and cable 13 function together to dissipate heatwhich the light energy generates from the lamp assembly 25 produces.

Referring to FIG. 2 in conjunction with FIG. 3 the focusing lens system26 includes a first lens 43, a sleeve 44, a second lens 45, a spring 47and a first C-ring 48. The first lens 43 is slidably coupled within thesleeve 44. The second lens 45 is also slidably coupled within the sleeve44. The cavity 22 of the body 21 of the light-tube 20 has a first ringgroove 49, a second ring groove 50, a first cylindrical portion 51, asecond cylindrical portion 52 and a third cylindrical portion 53. Thediameters of the first and third cylindrical portions 51 and 53 islarger than the diameter of the second cylindrical portion 52 therebyforming a first retaining cylindrical edge 54 and a second retainingcylindrical edge 55. The focusing lens system 26 is formed by insertingserially at a first end 56 the sleeve 44 with the first lens 43, thespring 47 and the second lens 45 inserted therein. The first C-ring 48is inserted and secured in the first ring groove 49. At a second end 57the reflector 23, the heat sensor 24 and a washer 58 are insertedserially. A second C-ring 59 is inserted and secured in the second ringgroove 50.

Referring to FIG. 2 in conjunction with FIG. 3 when the plug 31 isinserted in the socket 32 the optical fiber 30 is axially aligned withthe focusing lens system 26 of the light-tube module 20. The opticalfiber 30 extends to the end of the first small bore 39 of thedisc-shaped portion 38 of the heat sink, but does not extend into thelarge bore 40 thereof. The circuit board 28 has a plurality ofconductive lines 60 each of which is electrically coupled one of thereceptacles 37 of the socket 32. A disc-shaped piece 61 of insulatingmaterial, such as a plastic material, maintains the electricalseparation between the conductive lines 60 and the disc-shaped portion38 of the heat sink 33. When the heat sensor 24 detects excessive heaton the reflector 23 and within the cavity 22 of the body 21, the heatsensor 24 sends a signal to the processor 27 which turns off the lampassembly 25.

Referring to FIG. 2 in conjunction with FIG. 4 the body 21 of thelight-tube module 20 has a lamp bore 62, two top flanges 63 and anoutput bore 64. Each of the top flanges 63 has a socket bore 65. Thelamp assembly 25 includes two hollow insulating sleeves 66, two hollowconducting sleeves 67 and two insulated conductive wires 68. Each of thetwo hollow insulating sleeves 66 is inserted in the socket bore 65 ofone of the two top flanges 63. Each of the two hollow conducting sleeves67 is inserted in one of the two insulating sleeves 66. Each of the twoinsulated conductive wire 68 is electrically coupled to one of the twohollow conducting sleeves 67. The lamp assembly 25 also includes a cap69 which is formed out of an insulating material, such as plastic, andwhich has two pin bores 70, two conductive pins 71, two conductors 72and a light bulb 73 with two terminals 74. The light bulb 73 ismechanically coupled to the cap 69 and is adapted to be inserted intothe lamp bore 62. Each of the two conductive pins 71 is inserted in oneof the two pin bores 70 of the cap 69 and is adapted to be inserted intoone of the two conducting sleeves 67 so that each of the two conductivepins 71 can be electrically coupled to one of the two insulatedconductive wires 68. Each of the two conductors 72 electrically couplesone of the two conductive pins 71 to one of the two terminals 74 of thelight bulb 73.

Referring to FIG. 2 in conjunction with FIG. 6 and FIG. 7 the bottom 19of the housing 15 has four elongated slots 75. The body 21 of thelight-tube module 20 has four threaded holes 76 which are arranged inthe same manner as the four elongated slots 75. Each of four screws 77is loosely inserted into one of the four elongated slots 75 and threadedcoupled to one of the four threaded holes 76 in order to not only securethe light-tube module 20 in place, but also to provide focusadjustability of the light source 11 onto the optical fiber 30 bybi-directionally sliding the body 21 of the light-tube module 20 backand forth. The heat sink 33 is fixedly coupled to the socket 32, but isslidably coupled within the cavity of the body 21 of the light-tubemodule 20.

Referring to FIG. 8 a combination electronic iris and connector 110 isfor use with a light source 111 and an optical fiber 112 and includes aconnector 113. The light source 111 includes a light-tube module 120.The light-tube module 120 includes a body 121 with a cavity 122, areflector 123, a heat sensor 124, a lamp assembly 125 and a focusinglens system 126. The connector 113 includes a plug 131, a socket 132 anda heat sink 131. A CCD is optically coupled to the optical fiber 112.The focusing lens system 126 includes a first lens 143, a first sleeve144, a second lens 145, a second sleeve 146, a spring 147 and a firstC-ring 148. The first lens 143 is slidably coupled within the firstsleeve 144. The second lens 145 is slidably coupled within the secondsleeve 146. The cavity 122 of the body 121 of the light-tube 120 has afirst ring groove 149, a second ring groove 150, a first cylindricalportion 151, a second cylindrical portion 152 and a third cylindricalportion 153. The diameters of the first and third cylindrical portions151 and 153 is larger than the diameter of the second cylindricalportion 152 thereby forming a first retaining cylindrical edge 154 and asecond retaining cylindrical edge 155. The focusing lens system 126 isformed by inserting serially at a first end 156 the first sleeve 144with the first lens 143 inserted therein, the spring 147 and the secondsleeve 146 with the second lens 145 inserted therein. The first C-ring148 is inserted and secured in the first ring groove 149. At a secondend 157 the reflector 123, the heat sensor 124 and a washer 158 areinserted serially. A second C-ring 159 is inserted and secured in thesecond ring groove 150.

Referring to FIG. 8 in conjunction with FIG. 3 and FIG. 9 the processor28 includes an exposure control circuit which U.S. Pat. No. 5,258,848teaches. The combination electronic iris and connector 110 also includesan electronic iris 160. The CCD includes a substrate with a plurality ofcharge coupled devices and detector. The substrate is optically coupledto the optical fiber. The detector is optically coupled to the chargecoupled devices and electrically coupled to the electronic iris 160. Thedetector detects light intensity on the substrate and then either opensor closes the electronic iris 160 in a relative response thereto therebycontrolling the light intensity on said substrate. The socket 132 has athreaded bore and is mechanically coupled to the light source 111. Theplug 131 is adapted to be coupled to the socket 132 and has a bore forreceiving the optical fiber 112. The heat sink 133 has a disc-shapedportion having a bore for receiving the optical fiber 112 and a threadedstem portion having a bore for receiving the optical fiber 112. Thedisc-shaped portion of the heat sink 133 is slidably coupled to thelight source 111 and disposed adjacent to the socket 132. The threadedstem portion of the heat-sink 133 is threadedly coupled in the threadedbore of the socket 132. The optical fiber 112 is optically coupled tothe light source 111. The electronic iris 160 is disposed adjacent tothe bore of the threaded stem portion of the heat sink 133 and in thebore of the disc-shaped portion of the heat sink 133. The electroniciris 160 is axially aligned with the optical fiber 111. The electroniciris 160 is controlled by feedback from the CCD from the exposurecontrol circuit. The exposure control circuit includes a control amountconverting table which stores data on a gain control amount associatedwith data on a detected quantity of incident light and provides feedbackto the electronic iris 160. On the basis of an output from the controlamount converting table and light quantity gains of a light quantityvariable mechanism the exposure control circuit adjusts the electroniciris 160.

An automatic iris control system which U.S. Pat. No. 4,300,167 teachesis electrically adjustable. The automatic iris control system isconnected between a video camera and an optical input device whichproduces an optical image from a light directed upon and reflected froma subject. The optical image is directed onto the surface of anelectronic imaging tube in the video camera and the optical image has awide variation of reflected light due to variations in distance of thesubject from the light source. The automatic iris control system has amechanical iris and an iris drive motor which is located between thesurface of the electronic imaging tube and the optical input device andwhich dynamically varies the intensity of the optical image applied tothe electronic imaging tube of the video camera. A light intensityprogramming circuit establishes a desired light intensity level on thesurface of the electronic imaging tube of the video camera. An automaticiris control circuit has a low gain amplifier, a weighted peak responsedetector, a comparator, a circuit which control current to the irisdrive motor and a circuit which provides a feedback signal. The feedbacksignal represents the direction in which the iris drive motor mustadjust the mechanical iris in order to control the light intensity onthe surface of the electronic imaging tube of the video camera.

From the foregoing it can be seen that a lamp assembly for a lightsource has been described. It should be noted that the sketches are notdrawn to scale and that distance of and between the figures are not tobe considered significant.

Accordingly it is intended that the foregoing disclosure and showingmade in the drawing shall be considered only as an illustration of theprinciple of the present invention.

What is claimed is:
 1. A lamp assembly for a light source including abody having a cavity, a lamp bore, two top flanges each of which has asocket bore and an output bore, said lamp assembly comprising: a. twohollow insulating sleeves, each of said two hollow insulating sleevesbeing inserted in the socket bore of one of the two top flanges; b. twohollow conducting sleeves, each of said two hollow conducting sleevebeing inserted in one of said two insulating sleeves; c. two insulatedconductive wires, each of said two insulated conductive wire beingelectrically coupled to one of said hollow conducting sleeves; d. a capbeing formed out of an insulating material and having two pin bores; e.two conductive pins, each of said two conductive pins being inserted inone of said two pin bores of said cap and being adapted to be insertedinto one of said conducting sleeves so that each of said two conductivepins can be electrically coupled to one of said two insulated conductivewires; f. a light bulb with two terminals, said light bulb beingmechanically coupled to said cap and is adapted to be inserted into thelamp bore, said light bulb being optically aligned with the output bore;and g. two conductors, each of said two conductors electrically couplingone of said two conductive pins to one of said terminals of said lightbulb.
 2. A light source comprising: a. a body having a cavity, a lampbore, two top flanges each of which has a socket bore and an outputbore; b. a reflector disposed within said cavity of said body; c. afocusing lens disposed within said cavity of said body and opticallyaligned with said output bore of said body; and d. a lamp assemblyincluding: i. two hollow insulating sleeves, each of said two hollowinsulating sleeves being inserted in said socket bore of one of said twotop flanges; ii. two hollow conducting sleeves, each of said two hollowconducting sleeve being inserted in one of said two insulating sleeves;iii. two insulated conductive wires, each of said two insulatedconductive wire being electrically coupled to one of said hollowconducting sleeves; iv. a cap being formed out of an insulating andhaving two pin bores; v. two conductive pins, each of said twoconductive pins being inserted in one of said two pin bores of said capand being adapted to be inserted into one of said conducting sleeves sothat each of said two conductive pins can be electrically coupled to oneof said two insulated conductive wires; vi. a light bulb with twoterminals, said light bulb being mechanically coupled to said cap and isadapted to be inserted into said lamp bore, said light bulb beingdisposed within said cavity and optically aligned with said reflector;and vii. two conductors, each of said two conductors electricallycoupling one of said two conductive pins to one of said terminals ofsaid light bulb whereby said light bulb is optically aligned with saidfocusing lens.